This study will develop a home monitoring program based on a nursing assessment framework for patients with transplanted lungs. Home measurements will be made daily using a new electronic paperless spirometer/diary instrument. Patients do full spirometry daily at home, as they would when in the clinic pulmonary function laboratory. They also enter a full range of vital signs, symptomology and self-assessment of stress and well-being. Data is stored in the instrument's memory and is transmitted to the program data center over a standard telephone line each week. The measurements have been selected to be clinically useful in detecting the earliest signs of organ rejection or onset of opportunistic lung infection, the major causes of transplant failure. This will provide another mechanism to provide continuity of care into the home setting by delivering basic-patient interaction in training the patient to participate directly in the care of their chronic illness--the always present danger of developing chronic pulmonary rejection or opportunistic pulmonary infection. Weekly diary data will be entered into a computerized data base, and current weekly data, summary statistics and trend graphs of data submitted during previous weeks will be reviewed by the transplant care team each week for early detection of deteriorating condition. A decision system will be developed to automatically classify patients as either stable or showing early signs of infection/rejection. The early detection system will be evaluated by comparing rejection/infection onset calls with actual clinical status determined at regular scheduled or unscheduled clinic/hospital visits. This detection of early signs of rejection and/or infection will be completely automated so that the clinical care team will only have to review those cases flagged by the automated system as potential problem cases. This overall system will provide new knowledge useful for caring for all transplant patients, will prevent further disease progression, and mitigate the potentially disastrous effects of rejection and/or infection of the study population.